Compressor-unloading mechanism



C. OSGOOD Nov. 20, 19248.

lctmPmssoR uNLoAnING MECHANISM Filed nec. s1, 1925 vice.

Patented Nov. 20, 1928.

UNITED-STA TES lCHARLES F. OSGOOD, OF OIAREMONT, NEW`HAMPSHIREfASl-SIGNOR T0 ULLIYAN l MACHINERY COMPANY, .A CORPORATION OF IMASSAGEUSIET'IS.4

i' COMPRESSOR-UNLOADING, MEOHANISM. V

Application-filed December 3.1, 1923. Serial-No. 683,615. l

-- This invention relates to compressor unloading mechanism, and more particularly to means for controlling 'the same.

Ithas for its object to rovide an improved means for controlling tie unloading of the compressor. A further object is to provide an improved automatic means for controlling the unloading'of the compressor. Another object is to provide an improved means for controlling the unloading of the com ressor b speed responsive means. A still rther object is toprovide improved means whereb compressor engine`is brought up to speed. It is also an object of the invention to control the unloading of the compressor by a iiuid used in normal operation of thefcompresser or engine therefor. Another object is to provide improved controlling means of thehydraulic type which uses the cooling vwater for the compressor engine as the controlling iuid. It is another object of 'my invention to provide improved means whereby a usual and necessary accessory for the compressor en ine is used for controlling the unloading o the compressor. Another object is to provideimproved means whereby the compressor will be unloaded while the motor is being-bron lt up to speed and will also automaticallygb'e unloaded when a predetermined pressure in a receiver has been reached.

In the accompanying drawings I have shown for purposesof illustration one form which my invention may assume in practice.

Fig. 1 is a side elevation of .the whole de# Fig. 2 is an enlarged side elevation of a controlling valve and means for actuating the same, parts of-which are shown in section and other parts broken away tov facilitate illustration.

Fig. 3 is a detail sectional view through the inlet valve and unloading mechanism of one cylinder.

Fig. 4 is an enlarged centralxvertical section through a portion of the mechanism shown in Fig. 2. v

I propose to use my improved means for controlling unloading mechanism of a compressor 1 actuated by any suitable means, herein shown as a reciprocating engine 2, 4both of which are mounted uponl a portable frame 3 having wheels 4. Disposed on the front end of the frame 3 is a usual cooling radiator 5 having communciation as by pipes 6 and 7 with the cooling jackets 8 ofthe com-A I through the pipe 7 and discharge the'same outwardly through a pipe 10 and into the cooling jackets 8 through ay reduced bushing 11. The cooling fluid can thus flow from the cooling jackets as by pipe 12 to the cooling y jackets 13 of the compressor and back again the compressor will be unloadeduntilI the tosthe engine as by a pipe 14 and thence into the cooling radiator.

In order to unloadv the compressor,-I have conventionally shown at 15 a usual type of unloading mechanism comprising operating pistons, one of which is shown at 15, having operative vconnection with the inlet valves of the compressor one of which is shown at 15". Pressure fluid .is conducted from a"receiver 18 through pipes 17 and 16 to each piston, to actuate the same. To unload the compressor automatically, I propose to control the flow of fluid from the receiver 18 to the unloading mechanism 15 by two automatic devices arranged in parallel. One of these is a pilot valve 19 of the well known Judson type. 'Another of these is .a control which is made responsive to the pressure generated by the circulation pump 9, and to accomplish this a pipe 20 communicates at one end with the rals pipe 10 intermediate the pump 9 and reducf ing bushing 11 and at its opposite end with a chamber 21 formed in a hollow casing 22. Attached to a spring pressed diaphragm 23 disposed within the chamber 21 is an actuat ing rod 24 which projects outwardly through the casing 22 and is connected to a lever arm 25 as by a pin and slot connection 26. One end of the lever 25 pivots about a fixed point' 27, the pin and slot connection 26 being considerably closerto this end than to the other. The latter end of the arm 25 is connected by a pin and slot connection 28 to a valve actuating arm 29. The arm 29 is mounted upon a usual three-way valve 30 disposed in the lower end of the Judson valve 19. Any suitable gear reduct-ion means and couplings 31 can be disposed between the motor and compressor to positively drive the latter.

In the operation of my device, assuming the motor not running, the diaphragm 23 will A be pressed by its springy so as to cause the valve 30 to have the position as shown in Fig. 2,

i in which case pressure fluid from the receiver 18 will be by-passed around the controlling valve 19 to the pipes 17 and 16 to hold open the inlet valves of the compressor and thereby cause the latter to be unloaded when the en- I gine is started up. As the motor is brought up to speed, the rate of circulation of cooling water will be proportional thereto and as a result pressure will be increased within the pipe 10 due to the reducing bushing 11. It is understood, of course, that this bushing will not interfere with a normal circulation of cooling Water or other circulated liquid generally used around such mechanisms. It will of course ,also be understood that the reducing bushing may be dispensed with, if' a suflicient pressure is otherwise built up yin order to accomplish my result, but it is thought desirable to use a reducing bushing in order to get a finer degree of adjustment. As .pressure is built up, the diaphragm 23 will actuate the valve arm 29 to cut out the bypass around the Judson valve. lfVhen the engine is completely up to speed the bypass is completely cut out and the compressor loaded, for the pipes 16 and 17 will then be vented .to the atmosphere as is usual in the operation of a Judson valve thus releasing the Huid pressure on the unloading mech-v anism. It is also to be noted that in case the pressure in the receiver reaches a predetermined point, it will automatically actuate the Judson valve to unload the compressor without in any Way affecting the operation of the valve 30. Also when the engine is stopped, the pressure in the line 10 and 20 ,will be decreased and the arm 29 automatically thrown to the original position as shown in Fig. 2 as by the spring pressed diaphragm, thus permitting receiver pressure to actuate the unloading mechanism as originally described.

It will thus be seen'from ythe'operation of this device that I have provided an extremely simple means for controlling the unloading of the compressor due to the fact that I use the usualr and necessary elements of an engine and that by a few pipe connections and other small items I can readily attach my improved means to any standard engine and compressor outfit having an unloading mechanism, itbeing unnecessary in any way to provide special speed responsive devices, thus reducing the initial cost ofthe outlay to a minimum. can also place my diaphragm in anyposition convenient for the operation of the Judson valve 19 without any troublev at all for the pipe 20 may be bent to pass into any close quarters, whereas, if a mechanically actuated device were used, special linkages and supporting elements would be necessary.

While I have in this application specifically described one form which my invention may assume in practice, it will be understood that this 'form of the same is shown for purposes of illustration and that the invention may be modified and embodied in various other forms without departing from its spirit or the scope of the appended claims. p

What Iy claim is new and desire to secure by Letters Patent is:

1. The combination comprising a compressor having gaseous fiuid actuated unloading means, an engine for driving said compressor, means for normally circulating a cooling liquid for said engine the pressure of which increases with the speed of said engine, and means whereby said liquid controls actuation of said unloading inea-ns.

2. The combination comprising an engine having circulating means for a liquid usually associated therewith, a compressor having unloading meansincluding fluid pressure controlled devices confined in their control solely to said compressor and movable to effect substantially instantaneously complete unloading on fluid pressure flow relative thereto, and means whereby said unloading means is controlled by said circulating means.

3. The combination comprising a compressor, a. motor therefor, a liquid pump l v stopped.v f

5. The combination comprising a compressor having unloading mechanism, a receiver, a pilot valve responsive to receiver pressure for automatically unloading said compressor when a predetermined pressure in said receiver is reached, and fluid pressure actuated means for automatically bypassing said pilot valve to unload said compressor when the same is stopped.

6.l The combination comprising a compressor having unloading mechanism, a re- I ceiver,a pilot valve responsive to receiver pressure for automatically unloading said compressor when a predetermined pressure in said receiver is reached, and hydraulically actuated means for automatically bypassing said pilot `valve to unload said compressor when the same is stopped.

7. The combination comprising a compressor having unloading mechanism, a receiver, a pilot valve responsive to receiver pressure for automatically unloading said compressor when a predetermined pressure in said compressor until the same is brought up to normal speed.

8. The combination comprising a com pressor having unloading mechanism, a receiver, a pilot valve responsive to receive pressure for automatically unloading said compressor when a predetermined pressure in said receiver is reached, and means for automatically by passing said pilot valve to unload said' compressor, said means including a hydraulically actuated member, the 'luid for which is circulated in said compressor.

. 9. The combination comprising a compressor having unloading mechanism, a receiver, a ilot valveres onsive to receiver pressure or automatica ly unloading said compressor when a predetermined vpressure in said receiver is reached, and means for automatically bypassing said pilot valve to unload said compressor, said means including a hydraulically actuated member and means, which is normally operative in circulating a f supply of iuid, adapted to control said hydraulically actuated member.

,10. The combination of a compressor having a pressure fluid actuated unloader, a receiver, valvemeans for controlling flow of actuating fluid from said receiver to said unloading means to unload said compressor and for venting the Huid to the atmosphere to permit loading of said compressor, a pressure fluid actuated means for controlling said valve, and a usual liquid circulation system for said compressor, said latter means being automatically controlled by said liquid circulation system.

11. The combination comprising a compressor having unloading mechanism, a receiver, means for automatically actuating said unloading mechanism when a predetermined pressure in said receiver is reached, said means including a pilot valve between s a1d receiver and unloading mechanism, a 11qu1d pump driven by said engine whereby the pressure of the liquid pumped is proportional to the speed of the-engine, a second valve .for controlling fluid liow from said rece1ver to said .unloading mechanism, and

' means for actuating said latter valve by said liquid pressure to effect loading of said compressor.

12. yIn combination, a compressor, means movable to elect unloading thereof, a source of power medium, said means operable by said power medium, power medium transmitting means connecting said lirst mentioned'means and said source-including portions arranged in parallel, and speed responsive means controlling transmission in one of said portionsl and pressure responsive means controlling said other portion.

13. In combination, a compressor, discharge pressure controlled unloading means therefor comprising fluid operated means movable to efect unloading and discharge pressure controlled `means controlling fluid supply thereto, and compressor speed controlled means for controlllng fluid supply to said fluid operated means whereby said compressor may be started unloaded.

14. In an unloader .mechanism for compressors comprising a valve, the combination of a piston for moving the valve to eiiz'ect unloading, and controlling means for said piston including two independently controlled valve means, one discharge pressure controlled and the other controlled by the speed of the compressor.

15. In combination, a prime mover, a compressor driven thereby, unloading means for said compressor, a receiver for sai-d compressor, means responsive to the speed of the prime mover for controlling said unloading means, and means responsive to the pressure in said receiver independently of the speed of the prime mover for controlling said unloadi ing means.

16. In combination, a prime mover, a compressor driven thereby, a receiver, unloading means for said compressor, and a plurality of controls for said unloading means, one of said controls being responsive to the speed of the prime mover and another being responsive to receiver pressure independently of the speed of the prime mover. v

17. In combination, a prime mover, a com-l pressor driven thereby, a receiver, loading and i unloading means for said compressor having a servo-motor, and a plurality of controls for the operation of said servo-motor, one of said controls being responsive to the speed of the prime mover to cause the servo-motor to actuate the loading and unloading means and another being responsive to receiver pressure independently of the speed of the Iprimemover to cause the servo-motor to actuate the loading and unloadingmeans, said controls having common means for returning the servo-motor to initial position when the controls assume their initial position,

In testimony whereof I ailix my signature.

CHARLES F.. OSGOOD. 

